Both a head-on dorsal and ventral would probably be pretty helpful.
Didn't notice your commentary on the image until just now - it's still possible that it's an Aphonopelma sp. since at that size a lot of slings are still pretty pale. As small as it currently is, it may need to get some more size on it before anyone can make a guess accurate within a mile. If it IS Aphonopelma, you may have a heck of a time getting an ID on it since a lot of the genus look so similar.